The fight against unmanned vehicles is nothing new; however, especially with the arrival of new technologies that are easily accessible for the wider population, new problems are arising. The deployment of small unmanned aerial vehicles (UAVs) by paramilitary organizations during conflicts around the world has become a reality, non-lethal “paparazzi” actions have become a common practice, and it is only a matter of time until the population faces lethal attacks. The basic prerequisite for direct defense against attacking UAVs is their detection. The authors of this paper analysed the possibility of detecting flying aircraft in several different electro-magnetic spectrum bands. Firstly, methods based on calculations and simulations were chosen, and experiments in laboratories and measurements of the exterior were subsequently performed. As a result, values of the radar cross section (RCS), the noise level, the surface temperature, and optical as well as acoustic traces of tested devices were quantified. The outputs obtained from calculated, simulated, and experimentally detected values were found via UAV detection distances using specific sensors working in corresponding parts of the frequency spectrum.

The article focuses on the problem of aerial objects detection using various sensors and methods from the surface based air defence (SBAD) point of view. With the help of simulations it also proposes an optimal combination of active and passive radar and EO systems to ensure an adequate coverage of the Czech Republic. The analysis shows that the simulation of appropriate placement of sensors and their fusion can be beneficial not only for the real deployment phase but also for the better utilization of all the capabilities. The results of the simulations provide valuable insights for real deployment of sensors and SBAD assets, thus contributing to effective detection and protection of the Czech Republic's airspace. The article also contains number of pictures from the simulations of air strikes against selected objects in a simulation environment, where the possibilities of detection of air targets and the effectiveness of different sensor combinations are analyzed, including visualizations of radar coverage. Calculations of detection probabilities and effectiveness are also included. The aim is to show that there is no “silver bullet” solution and the choice of proper solution is usually use-case sensitive.